This invention relates to a pile driver powered by pressurized gas discharge and, more specifically, to a pile driver capable of delivering powerful thrusts to the pile being driven while submerged in deep water such as is frequently encountered in offshore ocean operations.
An airgun repeater powered pile driver capable of driving piles of various types and sizes and which can be operated totally submerged, partially submerged, or entirely in air is disclosed in my U.S. Pat. No. 3,817,335. The pile driver of the present invention provides further technological advantages, including unique gas and water purging features. The pile driver of the present invention can be advantageously utilized for driving long piles of large diameter in deep water work, for example, in water up to several hundreds of feet in depth, where submersion is highly advantageous in enhancing the driving characteristics for long piles. A large powerful pile driver embodying the present invention is capable of driving very long, large diameter pipe piles into the ocean floor, for example pipe piles 400 feet long or even 600 feet long or more and up to 4 feet and larger in diameter. The structure of the powerful deepwater pile driver embodying the present invention permits the gas discharging apparatus, also called an airgun, to remain in "floating" relationship without rigid attachment to the thrust-transmitting assembly in the pile driver thereby minimizing any potentially harmful effects of shock on the airgun which is used to power the driver. Thus, the pile driver of the present invention provides an operating capability and a structural arrangement of pile driver elements which is uniquely different from as well as providing numerous advantages over the airgun repeater powered and other pile drivers presently known. Another airgun powered pile driver is shown in my U.S. Pat. No. 3,646,598 and an airgun powered thruster in my U.S. Pat. Nos. 3,604,519 and 3,750,609.
I have also invented a prior pile driver method and apparatus as shown in U.S. Pat. Nos. 3,714,739; 3,788,402; and 3,721,095, which I believe to be quite different in principle and operation from a pile driver embodying the present invention.